Well drilling tool



Jan. 21, 1936. wm

WELL DRILLING TOOL Filed Apri1 a, 1953 frn/enfor' Jesse C. Wr/ghf WM fig Patented Jan. 21, 1936 I i Q i Q 2,028,579 WELL DRILLING TOOL Application April 3, 1933; Serial No. 664,106 seni rs. (01. 255-72),

This invention relates to awell drilling tool, wardly and outwardly to retracted positions to and relates more particularly to a device or permit the hard portionsof the core tofpass up means to be used in connection with a core re- Wardly into the body of the drill, and springs ceiving type of well drill that isoperable to normally yieldingly urging the cutters down into.

break up or cut away the core received by the efiective cutting engagement with the upper end. drill. A general object of this invention is to of the core.

provide a practical and effective means for de- Another object of theinvention is to provide stroying or cutting away the core in a core a tool of the character mentioned that includes receiving type of well drill. core catching means for retaining the hard It has been found that rotary well drills that p r i n o th c r in th d l so that th y 10 operate to make an annular 'cut in the earth may Withdrawn m the W With the drill! formation and then remove or break up the A further object of the hY h i i to p oremaining central core, are more rapid'and ef- Vide a e e v n oe e Cutting device of ficient in operation than drills that make a hole' the Character mentioned ti mpl j or bore of round cross section. Several forms xp nsiv of manufa tu a d that is su h t at 15 of devices for removing or breaking up the core may be d y embodiediin drills of va s. received in the first mentioned type of drill ohaleotelshave been introduced, but have not proved en- A further object of th invention is to P d tirely satisfactory. One type of core destroying a Simple d fi n We drill av utt or removingdevice that has been introduced inpa ts or'making an annular cut in the earth 2o volves a cutter rigidly attached to the drill and formation d't at inc udescuttersfor breaking operable to break up the core by making an ane l cutting y the p n of ,theeore' h nular out in its exterior. When hard earth are not eroded r Washed y y t e C laformations are encountered, the cutter in the tion. fluid, Said retractable ,olltters ng adap d NITED STATES" PATENT; oFricE type of device just mentioned, is not efiective to allow the y d p t Co to pas 25 in breaking up the core so that sections of the upwardly in the drill to be Wi drawn f om the core are broken loose from the formation at the WellWith the drillt t bottom of the well bore, become jammed in the 'Dther objects and features of the invention drill, and rotate with the drill and prevent the Will be fully understood from the o w n de- 3 proper engagement of the cutting parts of th tailed description of typical forms and applica- '30 drill with the formation, thus impairing the eftions of the invention, throughout which d ficiency of the drill. scription 'referenceis 'had to the accompanying An object of the present invention is to provide drawing, in Which: l i i a means or device for use in connection with a 1 S a een o u h d ta 8 core receiving type of rotary'well drill that is tiohal View of Well drill embodying O o l5 efiective in breaking up r cutting away t of thepresent invention showing the core derelatively soft, and the medium hard portions oy ng cutters in their'fully oper t v o i of the core, and that will allow the very hard 2 S an enlarged fragme t y horizontal e portions of the core to enter the drill without tionall View taken Substantially as indicated by 40 being broken away fr m th formation t t line 2-2 on Fig. 1. Fig. 3 is a verticaldetailed'40 bottom of the bore, so that hard sections of the sectional view taken asindiceted by ne;

core do not interfere with the proper opem on Fig. 2, and Fig. 4 is aside elevation of another tion of the drill. embodimentof the invention with one quarter Another object of the invention is to proin longitudinal cross S i y vide a core breaking or cutting means of the The tool device p d y t e P t 45 character mentioned that includes one or more invention may he used in Well drills Varying knives or cutters for acting on the core that are considerably in character, and in drills having retractable so as to allow the core to enter the v ous yp o Cu o t po drill intact when very hard earth formations are Through ut th fol wi d ta d s ptio 5 encountered. I will describe two embodiments of the inven- Another object of the invention is to provide tion in connection with a more or lesstypical a core cutting or removing means of the charcore receiving well drill, it being understoodthat acter mentioned that includes a cutter or cutthe inventionis not to be construed as limited ters pivotally mounted on the interior of the or restrictedto the specific forms or applica- 5 drill in a manner so that they may pivot uptions about tobe described, but is tobe taken 2 trated in the shoe ISis :stantially 90 as including any features or modifications that may fall within the scope of the claims.

The drill illustrated in the drawing includes a body ID to be attached to the lower end of an operating string of drill pipe, or the like, and adapted to receive a core or portions of a core. A sub H is provided on the upper end of the barrel l and has a tapered screw threaded pin l2 for facilitating connection of the drill with the operating string. A connecting member or sub l3 is threaded on to the lower end of the barrel l0 and has threaded pin M. The drill has a bit head I5 on its lower end for making an annular cut in the earth formation. The bit head I5 is connected to the lower end of the barrel l0 through the body of the core destroying means of-the present invention, which is interposed between the sub 13 and the bit head. The bit head l5 includes an annular or tubular shoe l6 provided with downwardly and outwardly projecting cutting parts or blades H. The opening l8 in restricted "at its lower end so that the softer portions of the core are eroded or washed away. The particular bit head shoe l6 illustrated in the drawing is provided'at its upper end with a threaded socket l9.

The embodiment of the present invention illus- Figs. 1, 2 and 3 inclusive of the draw.- ing, includes generally, a tubular body 20; adapted to be assembled in the drill between the sub l3 and the bit head l5, one or more retractable cutters 2| mounted in the body 2|l and operable to break upor cut away the core, means 22 for yieldingly urging the cutters 2| downwardly into cutting engagement with the upper end of the core, and core catching means 23 in the body 20 for retaining the harder portions or sections of core within the barrel 10.

The body 20 is in the nature of a-tubular connecting member or sub having comparatively heavy walls. A socket 24 is provided in the upper end of the body 20 to receive the screw threaded pin l4, and a pin 25 on the lower end of the body 20 is threaded into the socket l3 in the bit head. One or more longitudinal openings or slots 26 .are provided in the walls of the body 20. In the particular embodiment of the invention illustrated in the drawing, there are two comparatively long diametrically opposite slots 26, and shorter-slots 21 spaced subfrom the slots 26. Blocks 28 are welded or otherwise secured in the slots 26 to carry the cutters 2| and unitsof the core catching means 23'. Blocks 30' are provided in the slots 21 for carrying the other units of the core catching means 23.

The cutters 2| are provided to break up or cut away the core as it passes upwardly into the drill and are pivotally mounted so that they may retract in the event that the drill encounters very hard earth formations, and ahard portion of core passes into it. One or'more like cutters may be embodied in the device. In the embodiment of the invention being described there are two cutters 2|, one being carried by each of the blocks 28. The cutters 2| are in the nature of cutting blades or knives for acting on or cutting away the upper end of the core when the drill is rotated; The outer ends of the cutters 2| are pivotally mounted in diametrically opposite recesses 3| in the blocks 2|. Tangential openings 32 are provided in the wall of the body 20 and intersect the slots 26. Pins or screws 33 extend through the openings 32 and a downwardly projectingengagement with pass through transverse openings 34 in the outer end portions of the cutters 2|. The inner ends of the screws 33 may be threaded into openings 32, while the outer ends of the screws may be provided with socketed heads counter-sunk in the outer end parts of the openings. In' the preferred embodiment of the invention, the outer ends of the cutters 2| are rounded or cylindrically curved about the pivotal axes of the cutters, and correspondingly shaped seats are provided in the walls of the recesses 3|, so that the cutters may bear directly against the walls of the recesses. 3| are fiat and horizontal and are adapted'to be engaged by the lowersldes of the cutters 2| when the cutters are in their fully operative or horizontal positions. In accordance with the in vention, the recesses 3| are proportioned and formed to receive the cutters when they are in the retracted positions. The recesses 3| extend upwardly considerable distances from'the pivotal axes of the cutters, and have parallel vertical side walls against which the sides 'of the cutters mayjslidably bear. In the particular construction illustrated in the drawing, the inner walls 36 of the recesses 3| are flat and are inclined upwardly and inwardly relative to the vertical axis of the drill. The outer or upper sides of the cutters 2| are adapted to seat against the walls 36 when the cutters are in the fully retracted positions. If found practical or desirable, the cutters 2| and the recesses 3| may be proportioned and related so that the active portions of the cutters project into the core passing opening of the body 28 when the cutters are in their fully retracted positions against the walls 36. I

The cutters 2| are formed so that they shear or cut away the upper end of a core when in their'operative or partially operative positions during the drilling operation, that is, during rotation of the drill when the cutting parts l1 are acting on the formation at the bottom of the well bore. The forward lower edges 31 of the cutters-relative to the direction of rotation of the drill, constitute the cutting edges, and arecurved upwardly and outwardly to the inner ends ofthe cutters. The lower sides 38 of the cutters may be inclined downwardly to the cutinwardly to points at or immediately adjacent the central longitudinal axis of the drill, and the cutting edges 31 extend from points adjacent the walls of the body to the inner ends of the cutters so that the entire upper end of the core may be acted upon by the cutting edges of both cutters 2|.

The means 22 for normally yieldingly urging the cutters 2| downwardly into active cutting the upper end of the core are in thenature of'spring means. In the embodiment of the invention illustrated in detail in Figs. 1 and 2 of the drawing, the spring means 22 are located at the pivotal mountings of the cutters 2|. Longitudinal or radial slots 39 are provided in the outer ends of the cutters 2| and intersect the openings 34. Sleeves or tubes. 40 are arranged in the openings 34 and rotatably The lower walls of the recesses.

passer receive the screws 33. Helically wound springs ii are arranged in the slots 39 around the tubes 4|). sional strain, and each has an end reacting against the wall 36 and the inner wall of a slot 39. The springs 4| are operable to normally urge the cutters 2| totheir open or fully operative position and to yieldingly hold the cutters in active cutting engagement with the, upper end of the core. In practice, the springs 4| are sufliciently heavy or strong to hold the cutters 2| in engagement with the upper end of the core with enough pressure to insure the efilcient cutting action of the cutters. The tubes 40 carry the springs 4| so that the assemblies of the cutters 2|, tubes 40 and springs 4| may be readily arranged in the recesses 3| and mounted on the screws 33 as units.

The corecatching means 23 is operable to retain in the barrel I0, any hardsections of the core that pass the cutters 2| so that they may be removed with the drill. A plurality of core gripping and supporting'members 42 is provided on the body 20. In the form of the invention being described, core gripping and supporting members 42 are plvotally mounted in recesses 43 in the blocks 28 and 30 at points spaced above the cutters 2|. Pins 44 extend horizontally through the recesses 43 to pivotally support the upwardly and inwardly to the inner edges of the members to provide the members with sharp core gripping edges and to provide bevelled surfaces to be slidably engaged by the hard sections of core.

During the operation of the embodiment of the invention illustrated in Figs. 1, 2 and 3 of the drawing, the drill is rotated with its cutting parts H in engagement with the formation at the bottom of the well bore, and while circulation fluid under pressure is being discharged 4 downwardly through it. The cutting parts l| make an annular cut in the formation to provide a core that may pass upwardly through the restricted portion of the opening l8 with but slight clearance. The circulation fluid discharging from the restricted lower end of the opening |8 around the core erodes or washes away the softer portions of the core. The restriction at the lower end of the opening l8 increases the velocity of the discharging circulation fluid and thus provides for theeffective erosive action of the fluid. The hard or medium hard portions of the core that are not washed away by the circulation fluid pass upwardly into the body 20 and are acted upon by the cutters 2|. The springs 4| yieldingly urge the cutters 2| downwardly so that the cutters have effective cutting engagement with the upper end of the core. The two cutters 2|, in both being adapted to engage the entire upper end of the core may cut away the core as rapidly as the hole or bore is drilled by the cutting parts H. In the event that hard earth formations are encountered and the cutters 2| are not capable of cutting away the core as rapidly as it is received in the drill, the cutters are The springs 4| are under tor- The reforced upwardly and outwardly to their retracted positions. The hard section orsections of core that pass upwardly between thecutters 2| are received in the barrel H). of the drill and .when the drill has passed through the hard stratum,

the cutters 2| are again pivoted downwardly to their active positions by the springs 4|. In this manner, the circulation fluid washes away the softer portions of the core, while the cutters, 2|

are operable to cut away any remaining soft parts and. medium hard portions of the corebut are retractable to permit the ,very hard parts to pass upwardly into the barrel ID. The

core gripping and supporting members" are forced to the retracted positions by the hard portions of the core passing. upwardly into the I barrel l0." When thedrill is withdrawn from the well, the core gripping and supporting members 42 obtain firm holds on the hard adjacent portion or section of coretoretain the hard pieces of core in the drill so that they are withdrawn fromthe well with the drill.- Thecutters 2| in being retractable, permit'passage of the core upwardly into the barrel) when hard earth formations are encountered so that they do not interfere with the rapid operation of the tool. The cutting parts only'make an annular cut in the formation and are therefore rapid in their penetration of the formation.- The action of the circulation fluid together with the Lao cutting action of the cutters 2| normally destroy the core so that the drill is operable to penetrate the earth formation for agreatdistance'befora a quantity of core is received in the barrel Ill.

The form of the invention illustrated in Fig. 4 of the drawingincludes generally; a tubular body 53' adapted to be interposed in a core receiving drill, retractable cutters5| forcutting the core passing through the body 50, means 52 normally yieldingly urging the cutters 5| downwardly into.

mg a central longitudinal opening 54 and is provided at its upper end'with a threaded socket 55, and at its lower end with a threaded pin-54..

The body may act to interpose parts'of a drill in the same manner as the body 20. Circumferentially spaced longitudinal slots 56 are provided in the walls of the body 50 and carry blocks 51. In practice, there may be two diametrically opposite slots 56 and blocks 51. Shorter slots 58 carrying blocks 59 are spaced substantially 90 from the blocks 51. The cutters 5| are of substantially the same formation and are of the same proportion as the cutters 2|. The outer end portions of the cutters 5| are pivotally mounted in recesses 60 in the blocks 51 by'pins or screws 6|. The recesses 60 extend upwardly substantial distances from the pivotal axes of the cutters 5| so that they are adapted to receive the major portions of the cutters when in the retracted positions. The outer walls of the recesses 60 are inclined upwardly and inwardly as clearly illustrated in the drawing.

The means 52 for urging the cutters 5| to their operative positions and for yieldingly holding the cutters in cooperation with the upper end of the core are spaced from the pivotal axes of the cutters. Longitudinal openings 63 are provided in the blocks 51 in vertical alignment with the pivotally mounted outer ends'of the cutters 5|. The lower ends of the openings 53 open at the are slidable in the lower end portions of the openings 63. Springs 65 are provided in the openings 63 and are held under compression between the plungers 64 and the upper walls of the slots 56. Links 56 are pivotally connected to the plungers' 64 and the cutters 5|. Recesses 61 are provided in the upper sides of the cutters 5| to receive the lower end portions of the links 66. It will be apparent how the springs 65 acting through the links 66 normally tend to pivot the cutters 5| to their down or operative positions.

The core catching means 53 includes a plurality of pivotally mounted core gripping and retaining members 10. The core gripping and supporting members I are pivotally mounted inrecesses in the blocks and 59, being carried by screws or pivot pins 1|. In the embodiment of the invention disclosed in Fig. 4 of the drawing, the core gripping members are spaced below the cutters 5|. Springs 12 are provided to urge the members I0 to their down or core gripping positions.

The operation of the embodiment of the invention illustrated in Fig. 4 of the drawing is substantially the same as that of the form illustrated in Figs. 1 and 2. The cutters 5| are adapted to act upon the upper end of the core to cut away the core as it enters the drill. The springs 65 hold the cutters 5| in effective cutting engage ment with the core. Inthe event that a hard core is encountered, the cutters 5| may pivot upwardly to their outer retracted positions. After the hard portion of the core has passed upwardly into the barrel of the drill, the springs 65 again urge the cutters downward to their operative positions wherethey again cut away the upper end of the core-entering the drill. The core gripping and supporting members 10 are forced to their retractedpositions during the drilling operation, but are adapted to bite into the core when the drill is raised.

Having described only typical forms and applications of my invention, I do not wish to limit or restrict myself to the specific forms or applications above set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims.

a substantially vertical retracted position in the.

recess, thecutter having a cutting edgecurved upwardly and inwardly toward the longitudinal axis of the body, and means yieldingly urging the cutter to the substantially horizontal position.

2. A well drill including, a tubular body adapted to receive. a core, there being a recess in the inner wall of the body, a tubular cutting head on the lower end of the body for making an annular cut as the drill is rotated, a cutter for cutting away the core, means pivotally mounting the cutter in the recess so that it is shiftable between a substantiallyhorizontal position where it is adapted to engage the upper end of the core to cut away. the core as the drilling progresses and a substantially vertical retracted position in the recess, and means yieldingly urging the cutter to the substantially horizontal position, the last mentioned means including a spring in alongitudinal opening in the wall of the body, and means operatively connecting the spring and cutter.

3. A ,well drill including, a tubular body adapted to receive a core, there being a recess in the inner wall of the body, a tubular cutting head on the lower end of the body for making an annular cut as the drill is rotated, a cutter for cutting away the core, means pivotally mounting the cutter in the recess so that it is shiftable between a substantiallyhorizontal position where it is adapted to engage the upper end of the core to cut away the core as the drilling progresses and a substantially vertical retracted position in the recess, and means yieldingly urging the cutter to the substantially horizontal position, the last mentioned means including, a spring in a longitudinal opening in the body, a plunger slidable in the longitudinal opening and acted upon by the cutter, and a link pivotally connected to the cutter and plunger.

JESSEC. WRIGHT. 

